The last weeks storm cycle has drastically changed the snowpack adding a significant new load. Strong solar warming today will make the new storm slab more reactive.
Summary
Weather Forecast
Today we can expect a break from the stormy weather with a sunny day and building cloud in the afternoon. In the alpine the daily high will get up to -7*C, with freezing level to 1300m & winds from the east at 15kph. Tuesday will be more unsettled as a low moves across southern BC bringing light snowfall and 1900m freezing levels to Roger's Pass.
Snowpack Summary
Saturday's storm was the last in a series that brought heavy rain/snow, extreme winds (100+ km/h) and very warm temps. Widespread wind and storm slabs have formed at tree-line and alpine elevations as a result. Below approx. 1700m a rain crust is prevalent. This crust caps a moist upper snowpack.
Avalanche Summary
Natural and artillery controlled avalanches to size 4 were observed on Saturday. The biggest avalanche was Macdonald West Shoulder failing simultaneously in 4 start zones naturally, ripping out mature timber and running to the valley floor. Large fracture lines are visible in the backcountry showing wide propagation and multiple step down layers.
Confidence
Timing or intensity of solar radiation is uncertain